Molecular Mechanisms and Pathways as Targets for Cancer Prevention and Progression with Dietary Compounds

Abstract

A unique feature of bioactive food ingredients is their broad antioxidant function. Antioxidants having a wide spectrum of chemical structure and activity beyond basic nutrition; display different health benefits by the prevention and progression of chronic diseases. Functional food components are capable of enhancing the natural antioxidant defense system by scavenging reactive oxygen and nitrogen species, protecting and repairing DNA damage, as well as modulating the signal transduction pathways and gene expression. Major pathways affected by bioactive food ingredients include the pro-inflammatory pathways regulated by nuclear factor kappa B (NF-κB), as well as those associated with cytokines and chemokines. The present review summarizes the importance of plant bioactives and their roles in the regulation of inflammatory pathways. Bioactives influence several physiological processes such as gene expression, cell cycle regulation, cell proliferation, cell migration, etc., resulting in cancer prevention. Cancer initiation is associated with changes in metabolic pathways such as glucose metabolism, and the effect of bioactives in normalizing this process has been provided. Initiation and progression of inflammatory bowel diseases (IBD) which increase the chances of developing of colorectal cancers can be downregulated by plant bioactives. Several aspects of the potential roles of microRNAs and epigenetic modifications in the development of cancers have also been presented.

Anticancer potential of naturally occurring immunoepigenetic modulators: A promising avenue?

“…Furthermore, EGCG reportedly interferes with either HDAC or HAT activities and accordingly modulates protein acetylation levels . Similarly to other dietary phytochemicals, EGCG also modulates miRNA expression profiles in many cell types …”

“…Accordingly, resveratrol‐treated SIRT1 null mice develop tumors at normal rates . In addition, there is a large body of evidence demonstrating that resveratrol suppresses the expression of various oncogenic miRNAs and upregulates tumor‐suppressor miRNAs in various cancer models …”

“…32,71 Similarly to other dietary phytochemicals, EGCG also modulates miRNA expression profiles in many cell types. 14,75 Several studies have addressed whether the properties of EGCG could be exploited to counteract the tumor-induced suppression of immune responses or to stimulate antitumor immune responses. The first evidence of a tumor escape mechanism that could be inhibited by EGCG treatment emanates from a study revealing that EGCG inhibits IDO activity as well as IFN-γinduced IDO expression in colorectal cancer cells.…”

“…14 In addition, there is a large body of evidence demonstrating that resveratrol suppresses the expression of various oncogenic miRNAs and upregulates tumor-suppressor miRNAs in various cancer models. 75,83 The antitumor immunomodulatory properties of resveratrol have been highlighted in several studies and encompass the inhibition of immunosuppressive mechanisms in the TME and immune-enhancing properties. Resveratrol reportedly diminished Treg counts and functions ex vivo and in vivo, which are associated with the downregulation of TGF-β secretion from the spleen of EG7 lymphoma cell-induced and CT26 colon carcinoma cell-induced, tumor-bearing mice.…”

<strong>Evaluating medicinal plants for anticancer properties: testing plant extracts for cytotoxicity </strong>

“…Cancer development and progression has been described as exhibiting the following characteristics: (1) maintained proliferative signaling, (2) evasion of growth suppressors, (3) genomic instability and mutation, (4) replicative immortality, (5) avoidance of cell death, (6) tumor-promoting inflammation, (7) activation of invasion and metastatic pathways, (8) induction of angiogenesis, (9) reprogramming of cellular metabolism, and (10) escape from immune destruction [1]. Plants traditionally used for medicinal purposes contain a rich repository of bioactive compounds, which have the potential to therapeutically target these features of cancer biology [2]. [3][4][5][6][7][8][9][10].…”